Can I pass complex parameters to a Java Applet?

Question

I'm really new to Java and I have to create an applet for signing documents electronically. The applet will be called from an ASP.Net web page application.

Right now, I embed the applet in page as a <object id="EDOCApplet" classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93"> and send parameters to the applet like this:

<PARAM id="EdocPath" NAME="EdocPath" value="\\some\where\file.txt" />

In the applet, I can get the value using applet's built-in method getParameter("EdocPath");

What I need is the ability to pass the applet a list of several files and their "display names". For instance, it would be simple to write it down like an XML string:

<DocumentList>
  <UnsignedDocument Path="\\some\wehere\file1.txt" Description="Whatever comes here" />
  <UnsignedDocument Path="\\some\wehere\file2.txt" Description="Something else" />
...

However, as far as I see in HTML4.01 specification, the PARAM HTML element may not have content and it has no end-tag.

The choices I'm considering, are:

• html-encode the xml structure and send it to applet in a single PARAM object
• creating a list of PARAM objects and constructing their names like "File1", "Description1", "File2", "Description2", "File3"... then in Java applet create a while loop to read filenames while there is any.

However, none of the solutions seems to be elegant. The question is, what's the best practice in this case?

Answer 1

Pass them comma-separated:

<param id="files" name="files" 
     value="\\some\where\file.txt,\\some\where\file.txt" />

and then use String.split():

String[] fileNames = param.split(",");

In case of more complex structures you can use JSON to represent them.

Answer 2

You can also provide your applet with a public method:

initFile(String path, String description)

and call this method from javascript code (in which you can loop)

var applet = getElementByTageName(applet);
applet.initFile("yourPath","yourDescription");